Long-term patient reported outcomes following acetabular fracture fixation

Patient reported outcome scores may be the preferred method to assess clinical results following acetabular fracture fixation. However, in current acetabular fracture research, there is a scarcity of studies using these scores and long-term follow-up is lacking. The aim of this study is to describe long-term patient reported outcomes following acetabular fracture surgery and to evaluate the association between reduction quality and these outcome measures.

Patients who received operative fixation for acetabular fractures (1992-2012) were sent questionnaires (short musculoskeletal functional assessment (SMFA) function index and short form (SF)-12), which was returned by 106 patients (22%) (mean age 51 years, 74% male). Mean follow-up was 11.3 years and hip survivorship 78%. Reduction quality was assessed on postoperative CT or plain pelvic radiography (PXR) (3 patients). Reductions were graded as adequate (CT: <1 mm step and <5 mm gap/PXR: ≤3 mm displacement) or inadequate (CT: ≥1 mm step and/or ≥5 mm gap/PXR: >3 mm displacement). Outcome scores between native hip versus total hip arthroplasty (THA) and adequate versus inadequate reduction groups were compared and association between reduction quality and hip survivorship was determined. Subgroup analysis was performed in older patients (≥50 years).

Patients with native hips reported overall superior relevant outcome scores (SMFA function index (p = 0.047), mobility (p = 0.048) and SF-12 physical component (p = 0.008)) compared to THA patients. Hip survivorship was associated with adequate reductions (p = 0.019). In the native hip group, an adequate reduction was also associated with lower (better) clinical scores (exceeding the minimal clinical important difference) (MCID) specifically for SMFA function index (p = 0.117) and mobility (p = 0.022). In elderly patients, the native hip versus THA group had similar outcomes, and adequate reductions were associated with hip survivorship as well as superior clinical scores (at least exceeding the MCID) in those who retained their native hip.

At long-term follow-up, acetabular fracture surgery is associated with excellent patient reported outcomes. Patients who retain their native hip have overall superior relevant (SMFA and SF-12) function scores compared to those who convert to THA. Adequate reductions (on CT) were associated with both hip survivorship and superior outcome scores in patients who retain their hip.